Brain Core Temperature of Patients Before and After Orthotopic Liver Transplantation Assessed by DWI-Thermometry

Purpose The brain produces heat as a result of cerebral metabolism, and the heat is removed mainly through circulation of the intracranial blood vessels and cerebrospinal fluid (CSF). The aim of this study was to assess the brain core temperature of adult patients with end stage liver disease before and after orthotopic liver transplantation (OLT) using a noninvasive temperature measurement technique based on the diffusion coefficient of the cerebrospinal fluid. Materials and Methods This retrospective study used the data collected from January, 2014 to January, 2017. The study group comprised 19 patients (16 men, 3 women, mean age 57.9 ± 7.4 years) with a MELD score 23.7 who underwent magnetic resonance (MR) imaging before OLT and within 30 days after OLT. The etiology of end stage liver diseases was determined as follow: drug-related fulminant hepatic failure (n=1), nonalcoholic steatohepatitis (n=3), hepatocellular carcinoma (n=8), HCV/HBV/HDV infection (n=3), primary biliary cholangitis (n=1), acute liver failure on chronic sclerosing cholangitis (n=1), cryptogenic cirrhosis (n=1) and liver cirrhosis (n.=1). MR imaging studies were performed with a 1.5T MR scanner. Brain core temperature (T: °C) was calculated using the following equation from the diffusion coefficient (D) in the lateral ventricular (LV): CSF: T = 2256.74/ln (4.39221/D) - 273.15 using a standard DWI single-shot echo-planar pulse sequence (b value 1000 s/mm2). Statistical analysis was performed using a nonparametric Mann-Whitney U test. Results Brain core temperature measurements were successfully performed in all patients before and after OLT. Mean (± standard deviation) measured LV temperature was 38.67 ± 1.76 °C before OLT and 38.60 ± 0.99 °C after OLT, showing no significant difference (P = 0.643). Conclusions Brain core temperature was stable in patients undergoing OLT. Brain core thermometry using DWI-based MR imaging may provide a supplementary brain biomarker to confirm that cerebral blood flow and cerebral metabolism are stable during OLT.